An artist illustration of a meteor impacting the moon and resulting in an explosion that can be visible from Earth skies.
Credit: NASA

A boulder-sized meteor slammed into the moon in March, igniting an explosion so bright that anyone looking up at the right moment might have spotted it, NASA announced Friday.

NASA’s Meteoroid Environment Office is reporting the discovery of the brightest impact seen on the moon in the eight year history of the monitoring program.

Some 300 lunar impact events have been logged over the years but this latest impact, from March 17, is considered many orders of magnitude brighter than anything else observed.

“We have seen a couple of others in the ‘wow’ category but not this bright,” said Robert Suggs, manager of NASA’s Lunar Impact Monitoring Program at Marshall Spaceflight Center in Huntsville, Alabama.

The blast lasted only about a single second and shone like a 4th magnitude star—making it bright enough to see with just the unaided eye.

Frame from NASA telescope video capturing lunar flash on March 17, 2013. Credit: NASA/Robert Suggs

The NASA monitoring program’s 14-inch telescope was the first to snag an image of the lunar explosion. Analyzing the images, researchers estimate that the object probably weighed in at 40 kg (88 pounds) and was about 0.4 meters (1.4 feet) wide. It crashed into the moon at speeds of 56,000 miles (90,000 km) per hour, releasing as much energy as five tons of TNT.

Scientists hope to corroborate the impact with close-up photography from a NASA spacecraft  orbiting the moon.

“They are planning to image that location in hopes of finding the crater which would be very significant scientifically,” Suggs said.

On the same night as the impact, two fireball detection networks independently captured an unusually large number of bright meteors streaking through Earth’s skies. NASA scientists are working on a hypothesis that the Earth-moon system plowed through a stream of material that pelted both worlds with meteoroids.

But “this big impact doesn’t seem to be associated with any of the major showers,” said Suggs.

About half of the observed meteor strikes on the moon are thought to be associated with major meteor showers like the August Perseids and the December Geminds. (Related: Perseid Meteor Shower—And Moon Flashes—Peaks Saturday)

Backyard astronomers who have 8-inch or larger telescopes and equipped with video cameras can paricipate in NASA’s effort to capture lunar flashes. (See NASA’s guide to observing lunar flashes.)

The space agency uses the backyard-telescope data as part of its program to determine lunar meteor sizes and strike rates, data that could help prepare for potential long-term manned missions to the moon.

Astronaut Chris Hadfield poses with the Canadian flag in the Cupola module of the International Space Station (ISS). (Credit: NASA)

After returning to terra firma after five months aboard the orbiting International Space Station (ISS) with great fanfare, Canadian astronaut Chris Hadfield says he feels the drag of gravity and like he has aged quite a bit.

“It really feels like the day after I played a hard game of rugby or hockey…I am still tying to stand up straight,” said Hadfield at a news conference held at NASA’s Johnson Space Center today.

“When I got out of the capsule, I could actually feel the weight of my lips, and I didn’t realize that while in orbit I had learned how to speak with a weightless tongue.”

Hitching a ride on a Russian Soyuz capsule only a few days ago with his American and Russian crewmates, the 53-year-old is now in intense rehab of sorts at NASA’s Houston, Texas space center. Hadfield is going through a well-known adaptation period to Earth’s gravity after being weightless for such an extended time period.

“Chris feels like he’s an old man!” added Raffi Kuyumjian, the Canadian Space Agency’s chief medical officer and Hadfield’s flight surgeon.

Hadfield will have to endure a few more days of dizziness while trying to regain his manual dexterity as the blood flow in his body gets back to normal.

“He sometimes shuffles his feet when he walks, he is sore in his back, has difficulty walking around corners and sometimes hits the corners,” added Kuyumjian.

Researchers have discovered over five decades of spaceflight—and poking and prodding more than 500 astronauts in pre- and post-flight medical tests—that there are significant physiological changes the human body undergoes due to long periods of weightlessness. For example, astronauts typically lose one percent of their bone density per month—similar to what folks on Earth experience with osteoporosis over many decades of aging.

While living and working in space can wreak havoc on the human body, luckily, much of this damage can be corrected in about a year with special reconditioning programs.

“Scientists are using Chris as a subject for their science experiments in order to collect data to better understand these effects and how to treat them, which will be important for our aging population.” said Kuyumjian.

But while Hadfield conducted well over 100 science experiments during his stay in space, he will be remembered most by the general public as an internet sensation.

Over the course of his mission, Hadfield tweeted and YouTubed his way to celebrity status here on Earth, garnering nearly one million twitter followers and millions of views of his handy-cam videos. From posting his stunning images of Earth, chatting with actor William Shatner (aka Capt. Kirk of Star Trek), to filming some of his daily chores and singing songs, Hadfield became a prolific social media maven the likes of which space has never seen before. (Related: Live from Space, It’s the Videos of Chris “Space Oddity” Hadfield)

“The experience of leaving Earth is still quite new, and this was a way that a lot of people [could] share in the experience,” explained Hadfield.

“It’s just simply way too good of a thing to keep to yourself!”

In this image, the deep infrared glow of the orange hued ribbon shaped dust clouds is overlaid on a view of the region in the more familiar visible light,. The large bright cloud in the upper right of the image is the well-known Orion Nebula. Credit: ESO/Digitized Sky Survey 2

The Orion nebula  is one of the most favorite spots for stargazers to explore in the heavens, but this week astronomers are releasing a stunning new look to this giant stellar nursery 1300 light years from Earth.

A fiery cosmic ribbon glows with orange colors as grains of cold interstellar dust light up like a neon sign, shining bright in the far infrared part of the spectrum which is invisible to the human eye. This new image released by the European Southern observatory (ESO) shows this ribbon-like feature superimposed on a more familiar view of the cosmic clouds of dust visible in optical wavelengths.  (See also: Orion Nebula in Billion Pixel Beauty)

Thanks to the new views offered by the sub-millimeter (deep infrared) wavelength camera of the Atacama Pathfinder (APEX) telescope in the high deserts of Chile,  astronomers are able to peek behind this veil of cold dust that has been hiding hot, newborn stars in the more traditional views obtained in optical wavelengths. (Related: OMG Orion!)

The large white cloud in the upper right of the image is the famous Orion nebula- the brightest part of this star factory complex. It is a familiar sight for sky watchers as a fuzzy patch of light- the faint middle star of three that makes up the mythical hunter’s sword. In small backyard telescopes it looks like a ghostly grey flower in bloom.

Astronomers have combined the power of the Chilean telescope with the Herschel Space Observatory to comb this intense star formation region for signs of baby stars and sure enough they have been able to uncover 15 promising targets that glow in the far-infrared part of the spectrum. Astronomers believe these new dramatic views are finally giving them a glimpse at the earliest stages of star birth we have seen to date.

The moon pairs up with the bright star Regulus in the constellation Leo this week. Illustration by A.Fazekas/Starry Night Software

Moon, Jupiter, and Venus Lineup. On Monday, May 13, look for three worlds huddling very low in the western evening sky. From highest to lowest: The crescent moon, Jupiter below right, and Venus closest to the horizon. With the goddess of love setting only an hour or so after your local sunset, timing is imperative if you want to catch both planets together. (See Venus pictures.)

If  weather allows, try watching the planetary duo day to day through the rest of this month as Venus slowly climbs higher, culminating in a close encounter with Jupiter.

Arcturus, the Red Giant. After nightfall on Wednesday, May 15, gaze up at the orange-hued Arcturus, the brightest star riding high in the southeastern sky. Lying within the kite-shaped northern constellation Bootes, the herdsman, this dying red giant star sits nearly 37 light years from Earth. As a sky-watching bonus, look about 30 degrees to its lower right for Saturn and bright star Spica—both are about 30 degrees away from Arcturus, which is equal to three fist widths held at arm’s length. (See Saturn pictures.)

It’s worth training even the smallest small backyard telescope on creamy colored Saturn, as it can bring those majestic rings into clear focus.

The Lunar Wall. The first quarter moon coming into view on Saturday night is the best time of the month to view in small telescopes an amazing lunar feature called the lunar wall. A fault line that stretches 75 miles (120 kilometers) in length and is more than 1,300 feet (400 meters deep) casts a distinct straight and dark line through your eyepiece. (Read more about lunar wonders.)

The Straight Wall, or Rupes Recta, cuts across the face of the moon and is visible in small telescopes this week. Photograph courtesy JAXA/SELENE

Mercury At Dusk. Just after your local sunset Sunday, try to spot the the innermost planet in the solar system, Mercury. With the tiny planet only ten degrees from the western horizon this evening, you will need to have a clear line of sight right down to your local horizon with no obstructions. Binoculars will make it much easier to spot the faint, star-like world in the bright sunset glare.

Over the course of the next couple of weeks, watch as Mercury slowly climbs higher in the sunset sky as it approaches Jupiter and Venus.

Tell us—what cool sky phenomena have you seen lately?

A leak in one of the space station’s radiators requires a hastily planned spacewalk to assess damage and conduct repair. Credit: NASA

The crew aboard the International Space Station (ISS) is  preparing for a spacewalk Saturday as it deals with what NASA calls, “a serious leak” of ammonia coolant in a power system.

While NASA  officials in a news briefing  Friday afternoon said that the leak does not pose any danger to the six-person crew or the station, they have decided that “conditions are right” to send astronauts into the vacuum of space early Saturday to locate and assess the damage, and if possible make repairs.

Ammonia is used to cool the station’s seven separate power channels, which provide electricity to station systems. The malfunction is limited to one of those channels and has been powered down since it was  found this week.

A similar leak was detected last November and fixed via a spacewalk.  At that point the leak was measured at a manageable 5 pound of ammonia per year. This week’s new trickle unexpectedly skyrocketed to a loss of 5 pounds per day before it was shut down.

“The time is right to make the repair because the leak is big enough to visually identify the source,” said  ISS Program Manager Mike Suffredini on Friday.

The  leak was first discovered on Thursday when ISS Commander Chris Hadfield was looking out a window and told Mission Control he was seeing “a steady stream of flakes” coming out from the far left-side of the station’s truss structure, which holds the port-side solar panels.

Using hand-held cams and cameras mounted on the outside of the station, NASA was able to zero in on the location of the leak, which was about 150 feet from the main US airlock on the station.

“Big change in plans,” Hadfield tweeted on Friday, “spacewalk tomorrow (Saturday), Chris Cassidy and Tom Marshburn are getting suits and airlock ready. Cool!”

Marshburn and Cassidy, both U.S. astronauts, spent Friday prepping equipment and reviewing procedures for when they will open the hatch and begin their spacewalk at 7:15 am ET on Saturday.  Mission Control expects the entire operation to last at least 6 hours and 15 minutes.

The astronauts first will perform a visual inspection and attempt to pinpoint the leak. If they succeed they will attempt to manually replace  the 250-pound box that contains the malfunctioning coolant pump.

While all spacewalks have inherent risks, one of the concerns for Saturday has to do with avoiding icy flakes of ammonia floating around, which could contaminate their suits and lead to the poisonous chemical being brought inside the station.

NASA  is saying that all operations on the station can continue with one out of the seven power channels shut down. However if they would have to be down by another power system for a significant time it would create  challenges.

“It would not be critical in terms of a safety standpoint but it would impact science experiments,” explained Suffredini.

This is an artist’s impression of a a white dwarf with a disk of rocky debris left behind by the star’s surviving planetary system. Credit: NASA, ESA, and G. Bacon (STScI)

A pair of dead stars sitting in a star cluster about 150 light years from Earth appear to have their atmospheres polluted with debris from asteroids . Astronomers say this suggests that the basic ingredients for making Earth-like planets could be quite  common in stellar nurseries across the cosmos.

“We have identified chemical evidence for the Lego building blocks of rocky planets,” says Jay Farihi, lead author of a new study in a NASA statement .

The strange discovery was made thanks to the Hubble Space  Telescope’s view of two burnt-out cores of white dwarf stars. The orbiting observatory was able  to determine the chemical fingerprints of their stellar atmospheres and detect signs of silicon and carbon- known to be a common building blocks of rocky planets like our own. (Related: Solar System’s Fate Predicted by Nearby White Dwarf?)

Researchers believe that this polluting material is falling in from a population of asteroids orbiting in a disk around the stars which get pulverized as they get gravitationally sucked into the stars.

“When these stars were born, they built planets, and there’s a good chance they currently retain some of them. The material we are seeing is evidence of this,”  said Farihi, an astronomer at the University of Cambridge in England.

“The debris is at least as rocky as the most primitive terrestrial bodies in our solar system.”

The stars, reside in the Hyades star cluster, in the northern  constellation of Taurus (The Bull). The cluster is relatively young, at only 625 million years old. Until now, astronomers have had a hard time finding planets within young clusters like this because  the stars at this stage in their lives may simply be too active and unstable .

But now this new planet-detection technique is giving a never-before-seen peek at the actual chemistry of rocky planets.  What’s exciting is that just by looking at the ratio of silicon-to-carbon of the material they are measuring, researchers can tell how similar- chemically at least – exoplanets  could be to our own. (Related: New Planets found in Star Cluster- Would Have Dazzling Nights)

Astronomers now have a new tool in their arsenal to better understand the chemistry that goes into making planets, and figure out if there could possibly be different recipes for making habitable worlds like our own.

The polluted white dwarf study  appeared in the May 2 issue of the Monthly Notices of the Royal Astronomical Society.

The crescent moon will be paying a visit with Jupiter and Venus this week. Illustration via Starry Night Software/Andrew Fazekas

Here at National Geographic, we’ve discovered that readers love their space. So today we’re launching what we hope will be a far-out new feature: What to look for this week in the night sky. The second week in May will bring a mixed cosmic bag of shooting stars, an eclipse, and some worlds playing tag with each other.

Eta Aquarid Meteors. Starting at nightfall on Monday, May 6, straggler meteors from the Eta Aquarid shower should still be visible zipping through overhead skies across the globe. While rates of shooting stars will be significantly less than on peak night, May 5, it should be possible to see at least a half dozen per hour from dark skies throughout the first half of the week. (Also see: “Look Up for Halley’s Comet Shower This Weekend.”)

Venus Returns to Evening Skies. Starting on Tuesday, look for Venus—the second innermost planet—to start emerging from the evening twilight very low in the west-northwest. While it’s a challenge to hunt down within the sunset’s glare, Venus’ visibility will improve as it rises higher in the evening sky in following weeks.

Annular Solar Eclipse. On Thursday to Friday, the moon will cast its shadow on the Earth, making the sun appear as a ring of fire in the first solar eclipse of 2013. Visibility of the full eclipse can be seen from Queensland, Australia, on May 9 at 22:37 Universal Time and Papua New Guinea and the Solomon Islands at 23:00 UT. In Hawaii, a partial eclipse can be seen with just less than half the sun’s disc covered on May 10 at 1:50 UT. Here is a list of cities and times along the path of the eclipse. (See solar eclipse pictures from 2012.)

Moon Joins Venus. On Friday evening the very young and thin crescent moon passes Venus in the very low west-northwest horizon.  This pairing will be a challenge to observe because it will appear very low in the sky, so it’s best to find a location that has a free line of sight down the horizon. Venus will be only less than 2 degrees away from the moon—equal to the width of a thumb at an outstretched arms length. Binoculars will make it much easier to spot the cosmic pair in the bright twilight glare. (See Venus pictures.)

Moon Joins Jupiter. On Saturday and Sunday evening, watch the western sky at dusk for the waxing crescent moon to glide past Jupiter, the largest planet in the solar system. On Saturday the moon will be to the lower right of the gas giant. By Sunday the moon will have jumped to the upper left of the bright, star-like Jupiter. The two worlds will appear to be separated by about 6 degrees—a little more than the width of a fist held at an outstretched arm’s length.

Tell us—what cool sky phenomena have you seen lately?

Halley’s comet glides across the starry skies back in March 1986, shedding particles that will eventually approach Earth as Eta Aquarid meteors. Credit: NASA

Halley’s Comet won’t swing by Earth for another  48 years, but you won’t have to wait that long to watch bits of the iconic comet zip across our skies. That’s because this weekend Earth smashes into a stream of material, known as the Eta Aquarid meteors,  shed from the speedy iceberg in years past. (Related: Ancient Greeks Made First Halley’s Comet Sighting?)

Coming through the inner solar system every 76 years, Halley melts a bit from the heat of the sun and sheds some pounds as gas, dust, and rocks break off.  All this material then gets deposited in clouds of debris which follow the same orbit as the comet.

The result of this cosmic diet the comet undergoes is an annual shooting-star show, which this year is set to peak in the predawn hours of May 5, with rates of 10 to 50 meteors an hour – depending on local sky conditions.  Our planet plows through the densest part of Halley’s debris cloud Saturday night into Monday morning.

While not as spectacular as its August cousin, the Perseids, the cool factor for sky-watchers is that all those modest shooting stars are bits of debris from Halley’s Comet. One other shower – the Orionids in October – shares the same royal pedigree. (Related: See ‘Postcards’ from Halley’s Comet)

Eta Aquarids peak in the early morning hours of Monday radiating out from it’s namesake constellation. Credit: Courtesy of Starry Night Software/Andrew Fazekas

No telescopes or binoculars required to enjoy the show – just unaided eyes so that you can soak in as much of the overhead skies. The meteors will appear to radiate out from the constellation Aquarius – rising in the southeast around 3 am local time. Aquarids are known to be fast and bright, and because the waning crescent moon rises only around morning twilight,  skywatchers stuck in light polluted suburbs should be able to catch at least a dozen per hour early Sunday morning. Best views will be from the Southern Hemisphere with meteor counts decreasing as you head into the Northern Hemisphere – by mid northern latitudes Aquarids tend to be falling at a trickle.

Halley’s last paid a visit back in 1986 and won’t return until 2061, but with  some clear skies and patience, we can still marvel at its tiny but flashy, cosmic offspring this weekend.

Illustration of Herschel Space Observatory in front of its own infrared image of the star forming region known as the Rosette nebula. Credit: ESA – C. Carreau

After nearly four years of glorious service to science, the European Space Agency’s Herschel Space Observatory mission has come to the end this week. Running out of helium coolant needed to chill its instruments down to near absolute zero means that it has closed its far-infrared eyes to the Universe for good.  After a few final tests, controllers will park the retired probe in a permanent solar orbit.

Its mission was a far-reaching one – to study for the first time some of the coldest regions of space and examine the molecular chemistry of objects across the Universe- from distant galaxies and newborn stars to the atmosphere’s of gas giant planets and comets. (Related: Starburst Galaxy could Illuminate Early Universe)

But one of the stand-out legacies of Herschel, according to Michel Fich,  one of the of mission scientists, will be how the space telescope has provided a much greater understanding of the abundance of water outside of Earth and the solar system.

Herschel has helped provide answers in regards to how water may actually get onto planets, even habitable ones, like our own, says Fich.

“We believe that life requires water and all life as we know it is closely tied to its presence,” said Fich, astronomer at University of Waterloo, Ontario, Canada.

“So a question about life in the rest of the Universe has to start with questions like: Is there lots of water in the rest of the Universe? Is water found in high abundance in other solar systems?”

Here are Fich’s four picks for Herschel’s big watery discoveries.

1.  Cosmic reservoirs of water that pepper star birth regions

Herschel’s infrared view of part of the water-rich Taurus Molecular Cloud 450 light years from Earth. Credit: ESA/Herschel/SPIRE

Peering at a cosmic cloud of gas and dust  that is on the verge of collapsing and forming sun-like star and planets around it, Herschel discovered enough water vapor inside this nebula to fill Earth’s oceans more than 2000 times over.

This observation in the constellation Taurus is the first detection of water vapor in a cold molecular cloud,  and shows that there is a lot of water in the original clouds that will eventually form a star, and a solar system around it.

2.  Creating a solar system with a huge amount of water

Herschel detected copious amounts of cold water vapor, illustrated in blue in the above illustration, emanating from the star’s planet-forming disc of dust and gas. Credit: ESA/NASA/JPL-Caltech

This artist’s impression illustrates an icy protoplanetary disk around the young star TW Hydrae, located about 175 light-years away, where Herschel found a disk around the newborn star that is saturated with water.

This find for the first time shows that water can migrate from the original stellar cloud to the surrounding disk that may one day fragment into planets.

3.  Evolution of a comet system around a very young solar system

This Herschel image shows the infrared emission from the young star Fomalhaut and the dust disc surrounding it.that is believed to be formed through comet collisions. Credit: ESA/Herschel/PACS/Bram Acke, KU Leuven, Belgium

Herschel has studied the dusty belt around 25 light year distant star Fomalhaut and determined that it formed from the ongoing collision of thousands of icy comets..

The big questions facing astronomers now is if this cometary debris will go into making planets, is expelled from the solar system, or form comet belts?

4.  Supporting evidence for theory that the Earth’s oceans come from comets

This illustration shows the orbit of comet Hartley 2 in the Solar System. and Herschel’s image and the water data. Credit: ESA/AOES Medialab; Herschel/HssO Consortium

Herschel studied comet Hartley 2 using the most sensitive instrument to date for detecting water in space, and has shown that this cosmic iceberg is packed with water that has the identical molecular fingerprint as those found in Earth’s oceans.

The discovery revives the idea that our planet’s seas may have come from comets – presumably falling onto the Earth’s surface after the planet had already formed.  (See: What Created Earth’s Oceans: Comet Offers New Clue)

Hubble space telescope snaps detailed view of faraway comet ISON on April 10, 2013. Credit: NASA, ESA, J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team

Hubble has taken its first close-up views of the much anticipated and potential ‘comet of the century’. On the night of April 10th, the space telescope snapped an image in visible light of Comet ISON while it was still at a whopping distance of 394 million miles from Earth (386 million miles from the Sun)- a bit closer than the orbit of Jupiter. (See also: New Comet Found; May Be Visible From Earth in 2013)

While today it is only faintly visible as a fuzzy speck of light in large telescopes,  by end of November this year hopes are that ISON may briefly get as bright as the Moon in the sky.

Using the newly obtained Hubble data, astronomers estimate that the dirty snowball measures 3 to 4 miles wide, while the gas and dust filled coma that surrounds the nucleus stretches out approximately 3,100 miles in diameter – wider than the Australian continent.

Clearly visible on this new Hubble photo is the ghostly dust tail pointing away from the Sun, extending more than 57,000 miles. This iconic, ethereal feature of all comets form from  surface material being ejected at high speeds into space.

As comet ISON heads towards the Sun over the next few months,  the frozen surface of the nucleus will continue to warm up and melt. The Sun’s heat evaporates ices in the nucleus into jets of gases and dust, forming  the snowball-like coma – which, by the way, is slowly getting denser and wider as the comet approaches the Sun.
(Related :New Comet Discovered—May Become “One of Brightest in History”)

Astronomers believe that this may be ISON’s first trip into the inner solar system, coming from the far outer reaches of the solar system, from a frozen reservoir of billions of hibernating comets.  Based on orbital calculations, as the Sun’s gravity pulls in the comet,  it’s trajectory will take it uncomfortably close to the Sun on November 28.  In fact it will plunge within  700,000 miles of the fiery surface of our star before heading back out to the outer solar system and hopefully begin to put on a sky show.

So the big question on everyone’s mind now is – will ISON spectacularly light up our late autumn skies or will it fizzle- out and disintegrate as it dive bombs the Sun?  Time will tell.